The present invention relates generally to a fluid reservoir and more particularly to a ventless fluid reservoir for use with an internal combustion engine in a marine environment. However, it is contemplated as being within the scope of the invention that the disclosed device may be used in other environments, especially those types of environments in which there is a tendency for moisture or debris to be drawn into a conventional vented reservoir.
In the prior art, a known design for oil tanks used with outboard marine motors includes a generally rigid container of plastic or metal construction. In this prior art design, oil is withdrawn from the container by some type of pumping mechanism, which is typically driven by the engine. In order to maintain a constant pressure in the interior of the rigid container as the oil is withdrawn, a vent is normally provided on the container. Thus, as the oil is withdrawn from the container, air is pushed by atmospheric pressure through the vent and into the tank. In a marine environment, the ambient air may also contain significant amounts of moisture that may also be drawn into the container with the air, resulting in contamination of the oil and possible damage to the engine. In addition to the moisture problem, foreign material, such as seaweed, dust, debris or the like, may also be drawn toward the vent. This foreign material may cause problems in either of two ways. First, the foreign material may be drawn into the container through the vent and contaminate the oil and damage the engine. Second, the foreign material may block the vent, resulting in a reduction or elimination of the oil flow to the engine, which may also cause damage to the engine. While some of the problems associated with vents may be partially overcome through the use of screens, filters or other similar types of protective devices, these solutions have not proven entirely effective in eliminating the problems associated with vented fluid reservoirs.
Consequently, a primary object of the present invention is to provide an improved fluid reservoir that will not allow moisture or other foreign matter into the reservoir.
Another object of the present invention is to provide an improved fluid reservoir that does not require a vent, and thus eliminates the problems associated with vented reservoirs.
An additional object of the present invention is to provide an improved ventless fluid reservoir that is unaffected by moisture or foreign matter found in the surrounding environment.
Yet another object of the present invention is to provide an improved ventless fluid reservoir that is suitable for use in a marine environment.